# Overview

<Callout type="warning">
  Version **2025-09** is deprecated. New integrations should start on [2026-01](/docs/core/2026-01/guides/introduction/) instead - use the version switcher above to jump there. This version stays online, unchanged, for existing integrations mid-migration.
</Callout>

This page also sets frontmatter `seo.noindex: true` - it still builds and is reachable through normal navigation (the version switcher above), but renders `<meta name="robots" content="noindex, nofollow">` and is excluded from both `sitemap.xml` and `llms.txt`/`llms-full.txt`, since a deprecated version isn't content search engines or AI crawlers should treat as canonical.

The 2025-09 API covers the same widget resource as 2026-01, with two differences that motivated the newer version:

- No `color` field on widgets - it was added in 2026-01.
- Rate limit headers used the non-standard `X-Rate-Limit-*` prefix instead of `X-RateLimit-*`.

Both are additive/renaming changes only - if you're migrating, a widget response from either version can be read with the same client code as long as you don't depend on the fields/headers listed above.